We have already seen benefits of division axing, we are just unaware how bad situation would be if it didn't happen. Switch games of the, erm, highly polished visual quality take way more effort than their 3DS equivalents. (Wii U required similar effort to Switch.) It's kind of unpredictable what exactly the hypothetical 3DS successor would be; 3DS was really close to Wii with its expected visual quality, so the situation would likely keep getting worse unless Nintendo went and made a really cheap machine. The additional workforce is working, but there just is more work per game now.